ow it was circling the
field with its instruments set on the automatic signal for an emergency
pilot. They were worried and with good reason, for this flight carried
over 900,000 dollars worth of negotiable securities. But what could
attack one of those giant ships? It would take a small army to overcome
the crew of seventy and the three thousand passengers!

The great ship was landing gently now, brought in by the emergency
pilot. The small field car sped over to the plane rapidly. Already the
elevator was in place beside it, and as the officials in the car drew up
under the giant wing, they could see the tiny figure of the emergency
pilot beckoning to them. Swiftly the portable elevator carried them up
to the fourth level of the ship.

What a sight met their eyes as they entered the main salon! At first
glance it appeared that all the passengers lay sleeping in their chairs.
On closer examination it became evident that they were not breathing!
The ear could detect no heartbeat. The members of the crew lay at their
posts, as inert as the passengers! The assistant pilot sprawled on the
floor beside the instrument panel--apparently he had been watching the
record of the flight. There was no one conscious--or apparently
living--on board!

"Dead! Over three thousand people!" The field manager's voice was
hoarse, incredulous. "It's impossible--how could they have done it? Gas,
maybe, drawn in through the ventilator pumps and circulated through the
ship. But I can't conceive of any man being willing to kill three
thousand people for a mere million! Did you call a doctor by radio,
Pilot?"

"Yes, sir. He is on his way. There's his car now."

"Of course they will have opened the safe--but let's check anyway. I can
only think some madman has done this--no sane man would be willing to
take so many lives for so little." Wearily the men descended the stairs
to the mail room in the hold.

The door was closed, but the lock of the door was gone, the
magnesium-beryllium alloy burned away. They opened the door and entered.
The room seemed in perfect order. The guard lay motionless in the steel
guard chamber at one side; the thick, bullet-proof glass made his
outlines a little blurred, and the color of his face was green--but they
knew there too must be that same pallor they had seen on the other
faces. The delicate instruments had brought in the great ship perfectly,
but it was freighted with a cargo of dead!

They entered the